If you really need to know something about your camera it’s those three things. Aperture, exposure and ISO. Once you get familiar with these three, you’ll magicaly get out of the “amateur zone”.
Every camera uses aperture, exposure and ISO values to determine how your photo will look like. On auto mode it’ll set those up for you so your pic is sharp and well lit. But sometimes you want more blur in the background, don’t you? Or maybe you want your photo to be a bit darker to get this unique romantic feeling. Switch to the manual mode and continue reading.
Aperture is a hole that lets the light onto the sensor, through the lens of your camera. It’s the only value from those three that is determined by the lens you use. Look for a value that starts with f/… (f/1.4, f/2.8, f/4.6 etc.) That’s your lense’s minimum aperture value.
The lower the value, the wider the aperture can open and therefore it’ll let more light in a shorter time. Also, the lower value, the more blur you’ll get in the background and the more your subject will stand out from the background. See two pics below for example.
Or should I say shutter speed? This is a value that determines for how long the aperture stays open. The longer it’s open the more light it’ll let in. Usually a fraction of a second is enough for your photo to get well exposed.
In a well lit environment a 4000th of a second might be enough. Night photography, on the other hand, might require so called “long exposure” and aperture being opened for 30-60 seconds or even longer.
The faster your shutter speed is the better it’ll perform while shooting moving objects. When shooting a sport event you should keep the shutter speed as high as possible to keep the subjects in focus and avoid motion blur.
When shooting in a low light environment and using lower shutter speed values you should get a tripod, because the camera will register even a tiny shake and your picture will be blurred.
This value determines how sensitive camera’s sensor is to the light. The higher the value the more sensitive it is. The higher the ISO the less light you need to get your photo well exposed. But there is a downside.
Higher ISO values produce so called “noise” on your photos. A colourful grain that gets in the way of capturing a sharp and detailed picture. Modern cameras, however, have noise reduction features and generally produce less noise even with high ISO values.
How to combine those three?
First, if you haven’t yet, put your camera on full manual mode, the magic “M” on one of your dials. And then, just start experimenting. Change the aperture, shutter speed and ISO and see how it’ll affect your pics.
There is no better way to learn how to use those three values other than experimenting. Believe me, one day in manual mode is more than enough to get the basics. And then it’s just gets easier every day. You’ll eventually be setting these subconsciously.